T-5 behind an H-six?

[GB SISSON]

Is there any reason the S-10 version of the T-5 transmission wouldn't bolt up to a '51 H model flathead with the speedway or other kit? I have interchanged crashbox T-9s between the two engines. I'm quite familiar with shifting the T-9 but I'm seeing occasion where other family members are interested in taking it on dump runs and other errands. I have to also admit I have grown exceedingly fond of the T-5's silky gear changes in the truck based woodie.

[cas3]

If its a bolt up, I say go for it. Never know but if it had a modern tranny the family folk may think the old man and his old junk aint as goofy as we thought!

[woodburnranch]

I have a cheap S-10 4 speed without OD if you are interested.

[flatrod]

Years ago, I started on my project, I used a 6 cyl flathead pressed bellhousing on the back of a V8 flathead with a Mustang T5. I did put the S10 tail housing on the Mustang trans. The 6cyl bell was deeper than a V8 so no adaptors. The bottom two bolts go right in for the T5 but there is nowhere for the top bolts, so I was going to build that area up with weld. I never finished that project, but to me it looked like it was going to work.

[tubman]

Didn't "Ol' Ron" do something similar? As I remember, he added tabs for the top bolts.

It was a T170 : https://www.fordbarn.com/forum/showt...ng#post2310049.

[GB SISSON]

Sponsored Links (Register now to hide all advertisements)

See that? Ol Ron is still stepping up to the plate to help us out! Thanks guys for the input. I will have to look at what I have laying around for bellhousings. I do also have a couple of later year toyota landcruiser 4 speeds. Synchro on all four, but 1st isn't granny. The transfer case makes up for that. But really, the T-5 is what I should focus on. Are all stamped bellhousings the same?

[51504bat]

I'm no expert but IIRC the 1/2 bell on a 8ba V8 has a different bolt pattern than a flathead 6 1/2 bell.

[tubman]

Originally Posted by 51504bat

I'm no expert but IIRC the 1/2 bell on a 8ba V8 has a different bolt pattern than a flathead 6 1/2 bell.

I think you're right.

[cas3]

I think the tranny side is the same, the engine side is different, and the 6 bell is an inch or so thicker

[GB SISSON]

Originally Posted by cas3

I think the tranny side is the same, the engine side is different, and the 6 bell is an inch or so thicker

One inch thicker would explain why Ron didn't need the 1" plate that I made last year for the 8ba/T5. And bottom two bolts go right in... Then something akin to a couple of square nuts welded onto the stamped bell for the top bolts. Until I actually made a couple of aluminum plate trans adapters I marveled how anyone could get all those random bolts to line up and center things. Through my experimentation I learned the golden rule that the throw out bearing collar/tube and it's bolt flange at the tranny input end are the epicenter of all things transmission. I noticed on an aluminum '70s Ford BH that while these centers are a very nice fit, the bellhousing bolt holes were considerably oversized and the dowel pins if used and the register of the center took care of the critical alignment for me. This tonner is pretty low geared so I'd probably want a 5 sp OD, and on a truck I think prudent to go for the 'WC' World Class version from an S10.

[38 coupe]

I'm pretty sure the H series six cylinder engines in cars and trucks used identical transmissions to the same year V8s. Use of the H series bell housing and flywheel parts should end up with the same spacing and bolt pattern as the common 32-48 car and 32-52 truck transmission flange. Once that is done you can use the transmission adapter of your choice: home made, adapted from a later crash box, or specifically for the GM or Ford bolt pattern you want.

[tubman]

To put a early transmission behind an 8BA, you need an early Mercury or Ford truck bellhousing. Since there were no 6 cylinder Mercury's, it would seem you would need the bellhousing from a '48-'52 6 cylinder truck.

I guess I just said what "38 coupe" said, just in a "truck-specific" way.

[cas3]

The 6 cyl bells were stamped steel like the Mercs. GB must have one.

[GB SISSON]

Apparently I DO have one. It's sandwiched between the H six and it's crash box 4 speed. It's stamped steel. Am I correct that I wouldn't need something different than that one to work with? I could get a picture tomorrow.

[38 coupe]

You should be good to go with the bell housing already, assuming you used the later H series parts not the earlier G series parts.

The two big differences in swapping in a T5 to the tonner compared to the half ton will be that the cross member is deeper than it was in the half ton chassis, and that your driveshaft will be two piece in the tonner.

Take a look at the driveshaft situation, my memory is the tonner has the slip yoke in the rear part of the drive shaft after the carrier bearing. Is there a T5 with a bolt on companion flange? If not, make a plan for the drive shaft. Maybe the carrier bearing holds the whole thing in place (that sounds sketchy)?

I understand the desire to upgrade. I found a T98 to swap into my F-2 so I could have synchros on the normal driving gears. I just have a hard time picturing a T5 in a tonner, the lighter duty transmission doesn't seem like a match to the heavier duty pickup to me, but I'm odd that way.

[GB SISSON]

Originally Posted by 38 coupe

You should be good to go with the bell housing already, assuming you used the later H series parts not the earlier G series parts.

The two big differences in swapping in a T5 to the tonner compared to the half ton will be that the cross member is deeper than it was in the half ton chassis, and that your driveshaft will be two piece in the tonner.

Take a look at the driveshaft situation, my memory is the tonner has the slip yoke in the rear part of the drive shaft after the carrier bearing. Is there a T5 with a bolt on companion flange? If not, make a plan for the drive shaft. Maybe the carrier bearing holds the whole thing in place (that sounds sketchy)?

I understand the desire to upgrade. I found a T98 to swap into my F-2 so I could have synchros on the normal driving gears. I just have a hard time picturing a T5 in a tonner, the lighter duty transmission doesn't seem like a match to the heavier duty pickup to me, but I'm odd that way.

Thanks, lots of good info. The bell was on the h six when I got it so I think it's correct. And the light duty T-5, not at all odd to be suspicious there. I totally agree, just that for me I already have a vast array of heavy haulers ('92 F350 4x4 7.3 IDI ZF 5 spd man tran, '59 F 350 9' express w/ cummins 6cyl turbo and GM sm 465 man tran, two 3/4 ton 4x4 govt spec suburbans, the '99 has auto trans, '89 has factory sm 465 man trans, '97 chev 4x4 1/2 ton, the 4x4 Foyota, and probably a couple more) . In reality I have considered selling this six cyl tonner and finding a similar 1/2 ton jailbar for my 'old Pickup'. Then build another 276/T5/9" combo. Softer ride, tubeless tires, easy parking in town etc etc. Besides, I don't really have a project going right now and I find myself almost getting old and lazy. For instance, today I slept in til almost 7:00! In closing, the tonner has maybe 100 hp? and in Detroit they used the T5 in mustangs and camaros with V8s and kids burning rubber etc, just in case I got around to installing one in my avatar tonner, and drove it like an old man
Edit: The driveshaft might just go to a one piece with that long-tail T5, but still in the early stages here....

[38 coupe]

I would do some homework on the one piece driveshaft idea. The longer a driveshaft is the bigger diameter it has to be (read expensive), and still there is a maximum recommended length. This is to keep the driveshaft below its "critical speed", where it goes into harmonics. Spicer has an online calculator, there probably are others: https://spicerparts.com/calculators/...rpm-calculator